X-Git-Url: https://git.llucax.com/software/eventxx.git/blobdiff_plain/e956850cb32b3964152704e83db15fd93b157e43..890fc7e34047893c25951ae42a0b99af880ce2b5:/eventxx?ds=inline diff --git a/eventxx b/eventxx index d2846ec..ffbcf7e 100644 --- a/eventxx +++ b/eventxx @@ -1,7 +1,7 @@ #ifndef _EVENTXX_HPP_ #define _EVENTXX_HPP_ -#include // timeval (hack -> event.h don't include it) +#include // timeval #include // std::exception, std::invalid_argument, // std::runtime_error, std::bad_alloc @@ -9,10 +9,10 @@ * * @section Introduction * - * The libevent API provides a mechanism to execute a callback function when a - * specific event occurs on a file descriptor or after a timeout has been - * reached. Furthermore, libevent also support callbacks due to signals or - * regular timeouts. + * The libevent API provides + * a mechanism to execute a callback function when a specific event occurs on + * a file descriptor or after a timeout has been reached. Furthermore, libevent + * also support callbacks due to signals or regular timeouts. * * libevent is meant to replace the event loop found in event driven network * servers. An application just needs to call dispatcher::dispatch() and then @@ -27,24 +27,198 @@ * mechanism available on an operating system. Libevent should compile on Linux, * *BSD, Mac OS X, Solaris and Windows. * - * This is a simple, direct, one-header inline C++ wrapper for libevent. - * It's designed to be as close to use to libevent without compromising modern - * C++ programming techniques and efficiency (since all implementation is + * This is a simple, direct, one-header inline C++ wrapper for libevent. Yes, + * it's just one header file, so if you want to use it you can just copy the + * file to your project and you are set. + * + * It's designed to be as close to use to libevent (without compromising modern + * C++ programming techniques) and efficiency (since all implementation is * trivial and inline, theoretically, it imposes no overhead at all). * + * Please, visit the eventxx + * website for the latest documentation. + * + * You can always get the + * current + * release from the + * release + * directory or grab the + * most up to date + * sources from the darcs repository. + * + * You can also take a look the the darcsweb interface to see + * the latest + * changes online or subscribe to its + * RSS + * feed to follow the development. + * * * @section Usage * - * The best way to explain how this works is by examples. TODO + * This wrapper was designed to be used just like libevent, but with C++ style + * syntax sugar (or poison, depends on your point of view ;) and goodies. The + * main difference to libevent is you always have to instance a + * eventxx::dispatcher to get an event loop. There is no implicit global event + * loop. This adds just an extra line of code for single threaded applications + * and makes things much more simple. See eventxx::dispatcher documentation for + * more details. + * + * You can use use the same plain functions callbacks or the other kind of + * function objects (see @link events @endlink section for details on event + * types). + * + * eventxx uses @link exceptions @endlink to report errors. All functions has + * exception specifications, so it's easy to find out what to expect. See + * exceptions section for more detail. + * + * A timespec abstraction is provided in eventxx::time for convenient argument + * passing. Even more, it's a timespec itself, with some convenient methods for + * accessing the timespec attributes in a more C++ way. And even more, eventxx + * is such a direct mapping that all eventxx::event's are libevent event structs + * too, so theoretically you can pass a eventxx::event to libevent C functions + * without much trouble. eventxx::dispatcher is the only class that is not + * derived from libevent struct (event_base) because this struct it's not + * defined on the libevent header (just declared). + * + * Maybe you shouldn't know this implementation details to keep the abstraction, + * but this is a basic design goal of this wrapper so there is not much chance + * that this changes in the future (but use this knowledge with care, you are + * warned ;). + * + * @section Example + * + * @code + * #include + * #include + * #include + * + * struct handler + * { + * eventxx::dispatcher& d; + * int i; + * handler(eventxx::dispatcher& d): d(d), i(0) {} + * void operator() (int signum, short event) + * { + * if (i < 5) std::cout << "keep going...\n"; + * else + * { + * std::cout << "done!\n"; + * d.exit(); + * } + * } + * }; + * + * void sighandler(int signum, short event, void* data) + * { + * int& i = *static_cast< int* >(data); + * std::cout << ++i << " interrupts, "; + * } + * + * int main() + * { + * eventxx::dispatcher d; + * handler h(d); + * eventxx::csignal sigev(SIGINT, sighandler, &h.i); + * eventxx::signal< handler > e(SIGINT, h); + * d.add(sigev); + * d.add(e); + * d.dispatch(); + * return 0; + * } + * @endcode + * + * You can see some more examples on the test directory of the distribution or + * on the examples related page. + * + * + * @section Status + * + * This library was not widely used yet, it lack some testing. Because templates + * are not even compiled when they are used, you can't be surprised if you catch + * a piece of code that didn't got even compiled yet because the lack of + * testing. The library has no support for buffered events yet either. It + * doesn't support the http stuff, and probably never will because that has + * nothing to do with event handling. + * + * If you notice this lib leaks memory, don't blame me, blame libevent :) + * libevent has a known bug on event_base_free() that makes it assert always, so + * event_base_free() it's unusable, unless you patch your libevent (for example, + * using this patch + * written by Mark D. Anderson and who knows why it's not still applied. If you + * do so, you can compile your programs with -DEVENT_BASE_FREE_FIX so + * event_base_free() gets called. + * + * That said, I think it's pretty usable anyways. If something is broken it + * would be really easy to fix it because is just a simple wrapper around + * libevent. So, please try it out, and if you have any problems, + * drop me an + * e-mail and and I'll fix it ASAP (or provide a patch and you will be my + * best friend ;). + * + * Patches to support buffered events are welcome too. + * + * + * @author Leandro Lucarella * - * @author Leandro Lucarella * @version 0.1 + * * @par License - * This program is under the BOLA license (see - * http://auriga.wearlab.de/~alb/bola/) + * This program is under the BOLA license (see + * http://auriga.wearlab.de/~alb/bola/ for more info or the + * LICENSE + * file itself). + * + */ + +/** @example c-way.cpp + * + * This is a simple example illustrating the usage with C-like callback + * functions. + */ + +/** @example functor-way.cpp + * + * This is a simple example illustrating the usage with function object + * callbacks. + */ + +/** @example mixed-way.cpp + * + * This is a simple example illustrating the usage with a mix of C-like callbacks + * and function object callbacks. + */ + +/** @example bench.cpp + * + * This is a benchmark example, extracted from libevent and ported to eventxx. + */ + +/** @example prio-test.cpp + * + * This is a priority usage example. + */ + +/** @example test-time.cpp + * + * This is a timer usage example ported from libevent. + */ + +/** @example test-eof.cpp + * + * This is some kind of test of EOF ported from libevent. + */ + +/** @example test-weof.cpp * + * Another test of EOF ported from libevent. */ +/** @example trivial.cpp + * + * This is the most trivial example. + */ /** * Namespace for all symbols libevent C++ wrapper defines. @@ -60,7 +234,14 @@ namespace internal } -/// @defgroup exceptions Exceptions +/** @defgroup exceptions Exceptions + * + * eventxx makes a heavy use of exceptions. Each function has it's exceptions + * specified, so it's very easy to find out what exceptions to expect. + * + * Exceptions are mostly thrown when there is a programming error. So if you get + * an exception check your code. + */ //@{ @@ -101,7 +282,7 @@ struct invalid_event: public std::invalid_argument, public exception * Invalid priority exception. * * This exception is thrown when passing an invalid priority to a function. This - * usually means you don't have enought priority queues in your dispatcher, so + * usually means you don't have enough priority queues in your dispatcher, so * you should have allocated more in the constructor. * * If you hit this exception, you probably got a programming error. @@ -127,7 +308,7 @@ struct invalid_priority: public std::invalid_argument, public exception //@} -/// Miscelaneous constants +/// Miscellaneous constants enum { DEFAULT_PRIORITY = -1, ///< Default priority (the middle value). @@ -188,7 +369,20 @@ struct time: ::timeval }; // struct time -/// @defgroup events Events +/** @defgroup events Events + * + * There are many ways to specify how to handle an event. You can use use the + * same plain functions callbacks (see eventxx::cevent, eventxx::ctimer and + * eventxx::csignal) like in C or the other kind of more advanced, stateful + * function objects (see eventxx::event, eventxx::timer and eventxx::signal + * templates). The former are just typedef'ed specialization of the later. + * + * All events derive from a plain class (not template) eventxx::basic_event, one + * of the main utilities of it (besides containing common code ;) is to be used + * in STL containers. + * + * Please see each class documentation for details and examples. + */ //@{ /** @@ -291,7 +485,7 @@ struct basic_event: internal::event /** * Generic event object. * - * This object stores all the information about an event, incluiding a callback + * This object stores all the information about an event, including a callback * functor, which is called when the event is fired. The template parameter * must be a functor (callable object or function) that can take 2 parameters: * an integer (the file descriptor of the fired event) and an event::type (the @@ -431,7 +625,7 @@ struct signal: event< F > { /** - * Creates a new singal event. + * Creates a new signal event. * * @param signum Signal number to monitor. * @param handler Callback functor. @@ -506,7 +700,15 @@ typedef eventxx::signal< ccallback_type > csignal; /** * Event dispatcher. * - * This class is the responsable for looping and dispatching events. + * This class is the responsible for looping and dispatching events. Every time + * you need an event loop you should create an instance of this class. + * + * You can @link dispatcher::add add @endlink events to the dispatcher, and you + * can @link dispatcher::del remove @endlink them later or you can @link + * dispatcher::add_once add events to be processed just once @endlink. You can + * @link dispatcher::dispatch loop once or forever @endlink (well, of course you + * can break that forever removing all the events or by @link dispatcher::exit + * exiting the loop @endlink). */ struct dispatcher {